Q: What are the advantages and risks involved in buying a consolidator fare?
A: Consolidator fares (wholesale fares not listed on the major booking engines) are often cheaper than "published" fares, but there are risks involved in buying them. Consolidators have been known to go out of business, leaving consumers stranded. Plus, you may not get advance seat assignments or frequent flyer miles.
More importantly, often you must use a consolidator ticket on the exact dates and flights you originally purchased, with no changes allowed even if you wish to pay a penalty. It's use it or lose it. And if the fare goes down between the time you buy and the day of your flight, you may not be able to apply for a refund as you would, say, with an international fare bought directly from United Airlines (which refunds fare drops without extracting a fee).